Certification Problem
Input (TPDB SRS_Standard/Trafo_06/dup17)
The rewrite relation of the following TRS is considered.
a(a(a(a(x1)))) |
→ |
b(b(x1)) |
(1) |
b(b(a(a(x1)))) |
→ |
a(a(b(b(x1)))) |
(2) |
b(b(b(b(c(c(x1)))))) |
→ |
c(c(a(a(x1)))) |
(3) |
b(b(b(b(x1)))) |
→ |
a(a(a(a(a(a(x1)))))) |
(4) |
c(c(a(a(x1)))) |
→ |
b(b(a(a(c(c(x1)))))) |
(5) |
Property / Task
Prove or disprove termination.Answer / Result
Yes.Proof (by AProVE @ termCOMP 2023)
1 Dependency Pair Transformation
The following set of initial dependency pairs has been identified.
a#(a(a(a(x1)))) |
→ |
b#(b(x1)) |
(6) |
a#(a(a(a(x1)))) |
→ |
b#(x1) |
(7) |
b#(b(a(a(x1)))) |
→ |
a#(a(b(b(x1)))) |
(8) |
b#(b(a(a(x1)))) |
→ |
a#(b(b(x1))) |
(9) |
b#(b(a(a(x1)))) |
→ |
b#(b(x1)) |
(10) |
b#(b(a(a(x1)))) |
→ |
b#(x1) |
(11) |
b#(b(b(b(c(c(x1)))))) |
→ |
c#(c(a(a(x1)))) |
(12) |
b#(b(b(b(c(c(x1)))))) |
→ |
c#(a(a(x1))) |
(13) |
b#(b(b(b(c(c(x1)))))) |
→ |
a#(a(x1)) |
(14) |
b#(b(b(b(c(c(x1)))))) |
→ |
a#(x1) |
(15) |
b#(b(b(b(x1)))) |
→ |
a#(a(a(a(a(a(x1)))))) |
(16) |
b#(b(b(b(x1)))) |
→ |
a#(a(a(a(a(x1))))) |
(17) |
b#(b(b(b(x1)))) |
→ |
a#(a(a(a(x1)))) |
(18) |
b#(b(b(b(x1)))) |
→ |
a#(a(a(x1))) |
(19) |
b#(b(b(b(x1)))) |
→ |
a#(a(x1)) |
(20) |
b#(b(b(b(x1)))) |
→ |
a#(x1) |
(21) |
c#(c(a(a(x1)))) |
→ |
b#(b(a(a(c(c(x1)))))) |
(22) |
c#(c(a(a(x1)))) |
→ |
b#(a(a(c(c(x1))))) |
(23) |
c#(c(a(a(x1)))) |
→ |
a#(a(c(c(x1)))) |
(24) |
c#(c(a(a(x1)))) |
→ |
a#(c(c(x1))) |
(25) |
c#(c(a(a(x1)))) |
→ |
c#(c(x1)) |
(26) |
c#(c(a(a(x1)))) |
→ |
c#(x1) |
(27) |
1.1 Reduction Pair Processor
Using the linear polynomial interpretation over the naturals
[a#(x1)] |
= |
1 · x1
|
[a(x1)] |
= |
1 · x1
|
[b#(x1)] |
= |
1 · x1
|
[b(x1)] |
= |
1 · x1
|
[c(x1)] |
= |
1 + 1 · x1
|
[c#(x1)] |
= |
1 + 1 · x1
|
the
pairs
b#(b(b(b(c(c(x1)))))) |
→ |
c#(a(a(x1))) |
(13) |
b#(b(b(b(c(c(x1)))))) |
→ |
a#(a(x1)) |
(14) |
b#(b(b(b(c(c(x1)))))) |
→ |
a#(x1) |
(15) |
c#(c(a(a(x1)))) |
→ |
c#(x1) |
(27) |
could be deleted.
1.1.1 Monotonic Reduction Pair Processor
Using the linear polynomial interpretation over the naturals
[a(x1)] |
= |
1 + 1 · x1
|
[b(x1)] |
= |
2 + 1 · x1
|
[c(x1)] |
= |
2 · x1
|
[a#(x1)] |
= |
1 + 1 · x1
|
[b#(x1)] |
= |
2 + 1 · x1
|
[c#(x1)] |
= |
2 · x1
|
the
pairs
a#(a(a(a(x1)))) |
→ |
b#(x1) |
(7) |
b#(b(a(a(x1)))) |
→ |
a#(b(b(x1))) |
(9) |
b#(b(a(a(x1)))) |
→ |
b#(b(x1)) |
(10) |
b#(b(a(a(x1)))) |
→ |
b#(x1) |
(11) |
b#(b(b(b(x1)))) |
→ |
a#(a(a(a(a(a(x1)))))) |
(16) |
b#(b(b(b(x1)))) |
→ |
a#(a(a(a(a(x1))))) |
(17) |
b#(b(b(b(x1)))) |
→ |
a#(a(a(a(x1)))) |
(18) |
b#(b(b(b(x1)))) |
→ |
a#(a(a(x1))) |
(19) |
b#(b(b(b(x1)))) |
→ |
a#(a(x1)) |
(20) |
b#(b(b(b(x1)))) |
→ |
a#(x1) |
(21) |
c#(c(a(a(x1)))) |
→ |
b#(b(a(a(c(c(x1)))))) |
(22) |
c#(c(a(a(x1)))) |
→ |
b#(a(a(c(c(x1))))) |
(23) |
c#(c(a(a(x1)))) |
→ |
a#(a(c(c(x1)))) |
(24) |
c#(c(a(a(x1)))) |
→ |
a#(c(c(x1))) |
(25) |
c#(c(a(a(x1)))) |
→ |
c#(c(x1)) |
(26) |
and
the
rules
b(b(b(b(x1)))) |
→ |
a(a(a(a(a(a(x1)))))) |
(4) |
c(c(a(a(x1)))) |
→ |
b(b(a(a(c(c(x1)))))) |
(5) |
could be deleted.
1.1.1.1 Dependency Graph Processor
The dependency pairs are split into 1
component.